OpenTX 2.2.0 RC9 (N361) Improving your Tx

We are happy to bring you the 9th release candidate of OpenTX 2.2.0, with support for the production version of the FrSky Horus radio!

PLEASE NOTE the following important information before hastily jumping on it:

This is pre-release software. We’ve done our best to ensure its quality with main focus on the new Horus platform, with second priority on all Taranis versions (few changes from 2.1), then the other supported platforms, but we still expect there will be issues. As it is the purpose of a release candidate, we need your feedback to report things we may have missed.

There is currently no documentation other than this page, so get yourself a good coffee to wake up, and refer to the the great communities for help e.g. openrcforums here, RCGroups and threads like this one. You can pop in our chat room where other users and/or devs may be available.

Check during companion install that it installs itself in the correct directory, usually you want “Companion 2.2”. A bug that will still show up on this update may cause it to install itself in “Companion 2.1”, potentially overwriting your 2.1 install.

Companion supports reading and writing Horus firmware when the radio is powered off and then connected to USB, using dfu-util and the libusb drivers installed by Zadig, exactly like for the Taranis. See the “Flashing your Taranis Radio” section in this manual. Companion can back up existing firmware (see note below in known issues) including the stock FrSky one (save as .bin), and can flash the FrSky DFU bootloader so that no other tool and/or driver swapping is needed. You might need to disable the “Check hardware compatibility” checkbox in the flashing dialog.

SD card contents can be found here. Download the correct archive for your radio type, extract it to the root of an empty SD card and you’ll have all needed files. Please note that all existing OpenTX sound packs won’t work due to changes in the naming strategy, so you’ll likely want to use those that are included in this archive until popular 3rd-party packs are adapted.

OpenTX does not touch the internal flash of production Horus radios. Its contents do not need to be backed up and are not accessible in any way when OpenTX firmware is loaded.

There is no bootloader on Horus at this point. The SD card can be accessed while the radio is powered on, providing you selected the “massstorage” firmware option.

If you are using a beta Horus and are not starting fresh (i.e. you keep your models and settings from a previous OpenTX nightly) you will need to reconfigure pot types on the Radio->Hardware page and recalibrate your sticks and pots.

Known issues:

Companion installer may try to install itself in the wrong directory, see above.

The progress bar in companion when reading firmware from a Horus is broken and will reach 100% at only 25% progress. Just wait, the window will close when the process is finished.

Download and install Companion and use it to retrieve and transfer the latest OpenTX firmware to your radio after configuring the proper radio type.
You need to check “Use OpenTX firmware nightly builds” in companion settings to be able to download firmware, and “Use companion nightly builds” to be notified of further companion release candidate updates.

Horus production version and beta version use different hardware. Companion defaults to production hardware, for beta radios check the “pcbdev” firmware option in the profile settings.

Changes since 2.2.0 RC8

ARM : PPM_LIMITS_SYMETRICAL(symlimits), PPM_CENTER_ADJUSTABLE(ppmca) and CURVES are now included on all ARM platforms.